The WSJ has been talking to a couple of startups working in this field, including 6SensorLabs which has a device that can – with the help of a smartphone – detect whether a food really is gluten-free.

The Nima from 6SensorLabs is an organic-chemistry lab small enough to carry in your pocket. Right now it is only good for one thing: detecting gluten in foods at minuscule concentrations, as little as 20 parts per million, the FDA’s threshold for declaring a food “gluten-free.”

The company says that this could be just the start, with future versions able to detect the bacteria that cause food poisoning …